This compound belongs to the penicillins. These are organic compounds containing the penicillin core structure, which is structurally characterized by a penam ring bearing two methyl groups at position 2, and an amide group at position 6 [starting from the sulfur atom at position 1].

Pharmacology

Indication

Used to treat infections caused by penicillinase-producing staphylococci which have demonstrated susceptibility to the drug.

Pharmacodynamics

Dicloxacillin is a beta-lactamase resistant penicillin similar to oxacillin. Dicloxacillin has in vitro activity against gram-positive and gram-negative aerobic and anaerobic bacteria. The bactericidal activity of dicloxacillin results from the inhibition of cell wall synthesis and is mediated through dicloxacillin binding to penicillin binding proteins (PBPs). Dicloxacillin is stable against hydrolysis by a variety of beta-lactamases, including penicillinases, and cephalosporinases and extended spectrum beta-lactamases.

Mechanism of action

Dicloxacillin exerts a bactericidal action against penicillin-susceptible microorganisms during the state of active multiplication. All penicillins inhibit the biosynthesis of the bacterial cell wall. By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, dicloxacillin inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that dicloxacillin interferes with an autolysin inhibitor.

Absorption

Absorption of the isoxazolyl penicillins after oral administration is rapid but incomplete: peak blood levels are achieved in 1-1.5 hours. Oral absorption of cloxacillin, dicloxacillin, oxacillin and nafcillin is delayed when the drugs are administered after meals.

Volume of distribution

Not Available

Protein binding

Binds to serum protein, mainly albumin.

Metabolism

Route of elimination

Dicloxacillin sodium is rapidly excreted as unchanged drug in the urine by glomerular filtration and active tubular secretion.